Quantum Engineers Find a Use For the Hashtag at the Nanoscale

A nano-hashtag structure at scales of a billionth of a meter should help Majorana fermions be more easily manipulated into a topological quantum bit, or qubit: the building block for quantum computers.

Credit: Technical University Eindhoven

Researchers at the University of Sydney in Australia are building next-generation quantum-engineered devices based on quasiparticles called Majorana fermions, whose existence was recently validated by the efforts of researchers at the Technical University Delft in the Netherlands.

The Delft team proved that electrons on a one-dimensional semiconducting nanowire will possess a quantum spin opposite to its momentum in a finite magnetic field.

"This information is consistent with previous reports observing Majorana fermions in these nanowires," says Maja Cassidy, a senior researcher at Microsoft's Station Q Sydney, based at the University of Sydney Nanoscience Hub.

Quantum bits (qubits) that use Majorana fermions will have their information encoded via their geometry, or topology.

The braiding of the Majoranas promises to encode quantum information in a manner that is highly resistant to interference.

The University of Sydney team is working with Microsoft Station Q engineers to build the new devices, which are designed to function as the core of the first practical topological quantum computers.